Dao Cao - Academia.edu (original) (raw)

Papers by Dao Cao

Journal of Physics: Conference Series, 2009

Silica xerogels containing nanocarbon were milled for several hours before the carbothermal reduc... more Silica xerogels containing nanocarbon were milled for several hours before the carbothermal reduction processing. The formation of SiC nanorods was investigated at different annealing temperatures. It is shown that the formation temperature of SiC nanorods can be decreased if the powder size of milled silica xerogels is lower than 100 nm. The morphology, structure and production efficiency of synthesized SiC were determined by scanning electron microscopy SEM, X-ray diffraction XRD and thermo-gravimetric analysis TGA measurements. It is evident that production efficiency of synthesized SiC nanorods clearly depends on uniformity of precursor materials.

International Journal of Nanotechnology, 2011

SiC nanorods were synthesised from SiO 2 xerogel containing carbon nanoparticles at 1550° C in ar... more SiC nanorods were synthesised from SiO 2 xerogel containing carbon nanoparticles at 1550° C in argon flow. The morphology and structure of the materials were determined by transmission electron microscopy, scanning electron microscopy, X-ray diffraction and ...

Communications in Physics, 2007

The results on elemental analysis of the vietnamese ancient bronze coins during the time of the N... more The results on elemental analysis of the vietnamese ancient bronze coins during the time of the Nguyen dynasty (19th century) are presented. The samples were provided by the Vietnam National Historical Museum and the elemental analysis was performed on the home-made model EDS-XT-99-01 X-ray fluorescence spectrometer in the Institute of Materials Science, NCST of Vietnam. The samples exited simultaneously by radioisotope source and X-ray tube. The analytical results show the similarity in the elemental composition of the coins issued by different kings of the Nguyen dynasty, but there is the difference in the concentration of the used elements. Another interesting point is that all the coins have zinc (Zn) in their composition, which shows clearly the influence of the occidental metallurgical technology on the money-making technique in Vietnam during the 19th century.

Time-resolved luminescence spectra (TRLS) of porous silicon (PS) in the delay time range of 10-9-... more Time-resolved luminescence spectra (TRLS) of porous silicon (PS) in the delay time range of 10-9-10-6 s were investigated. The luminescence spectra include the blue zone with decay time of the order of nanoseconds and the red zone with longer decay time. Recombination mechanisms in the core and in the surface states were used to explain this experimental result. The existence of discrete peaks in the blue zone shows that the luminescence is due to nano-scale crystals

Journal of Physics: Conference Series, 2009

Porous amorphous SiC (a-SiC) layer with pore size in the nanometer region was fabricated on the a... more Porous amorphous SiC (a-SiC) layer with pore size in the nanometer region was fabricated on the a-SiC/Si substrates by the electrochemical etching method using HF/H2O/surfactant solution. Systematic study showed that the HF concentration in the etching solution (in the 1-73% region) strongly affects the structure (both the pore size and the pore density) of the porous a-SiC layer. It was also observed the changing of the photoluminescence properties of the porous a-SiC layer when its structure has been changed.

Journal of Physics: Conference Series, 2009

The study on co-deposition of Ni-nano SiC in sulphamate bath was conducted with different nano Si... more The study on co-deposition of Ni-nano SiC in sulphamate bath was conducted with different nano SiC concentrations from 1 to 20 g/l. The deposition of light inert SiC nanoparticles in Ni plating was investigated by scanning electron microscopy SEM and X-ray dispersive spectrometer EDX measurements. The microhardness and corrosion resistance were also measured to evaluate mechanical and corrosion properties of Ni-nano SiC coating on metal.

Journal of Physics: Conference Series, 2009

... Huynh Thi Ha1, Cao Tuan Anh2, Nguyen Thi Thu Ha1, Phan Viet Phong1, Dao Tran Cao1, Le Quang H... more ... Huynh Thi Ha1, Cao Tuan Anh2, Nguyen Thi Thu Ha1, Phan Viet Phong1, Dao Tran Cao1, Le Quang Huy1 and Nguyen The Quynh1 1 Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay Distr., Hanoi, Vietnam 2 ...

Journal of Physics: Conference Series, 2009

The study on co-deposition of Ni-nano SiC in sulphamate bath was conducted with different nano Si... more The study on co-deposition of Ni-nano SiC in sulphamate bath was conducted with different nano SiC concentrations from 1 to 20 g/l. The deposition of light inert SiC nanoparticles in Ni plating was investigated by scanning electron microscopy SEM and X-ray dispersive ...

Journal of Physics: Conference Series, 2009

Journal of Physics: Conference Series, 2009

Silica xerogels containing nanocarbon were milled for several hours before the carbothermal reduc... more Silica xerogels containing nanocarbon were milled for several hours before the carbothermal reduction processing. The formation of SiC nanorods was investigated at different annealing temperatures. It is shown that the formation temperature of SiC nanorods can be decreased if the powder size of milled silica xerogels is lower than 100 nm. The morphology, structure and production efficiency of synthesized SiC were determined by scanning electron microscopy SEM, X-ray diffraction XRD and thermo-gravimetric analysis TGA measurements. It is evident that production efficiency of synthesized SiC nanorods clearly depends on uniformity of precursor materials.

International Journal of Nanotechnology, 2011

SiC nanorods were synthesised from SiO 2 xerogel containing carbon nanoparticles at 1550° C in ar... more SiC nanorods were synthesised from SiO 2 xerogel containing carbon nanoparticles at 1550° C in argon flow. The morphology and structure of the materials were determined by transmission electron microscopy, scanning electron microscopy, X-ray diffraction and ...

Communications in Physics, 2007

The results on elemental analysis of the vietnamese ancient bronze coins during the time of the N... more The results on elemental analysis of the vietnamese ancient bronze coins during the time of the Nguyen dynasty (19th century) are presented. The samples were provided by the Vietnam National Historical Museum and the elemental analysis was performed on the home-made model EDS-XT-99-01 X-ray fluorescence spectrometer in the Institute of Materials Science, NCST of Vietnam. The samples exited simultaneously by radioisotope source and X-ray tube. The analytical results show the similarity in the elemental composition of the coins issued by different kings of the Nguyen dynasty, but there is the difference in the concentration of the used elements. Another interesting point is that all the coins have zinc (Zn) in their composition, which shows clearly the influence of the occidental metallurgical technology on the money-making technique in Vietnam during the 19th century.

Time-resolved luminescence spectra (TRLS) of porous silicon (PS) in the delay time range of 10-9-... more Time-resolved luminescence spectra (TRLS) of porous silicon (PS) in the delay time range of 10-9-10-6 s were investigated. The luminescence spectra include the blue zone with decay time of the order of nanoseconds and the red zone with longer decay time. Recombination mechanisms in the core and in the surface states were used to explain this experimental result. The existence of discrete peaks in the blue zone shows that the luminescence is due to nano-scale crystals

Journal of Physics: Conference Series, 2009

Porous amorphous SiC (a-SiC) layer with pore size in the nanometer region was fabricated on the a... more Porous amorphous SiC (a-SiC) layer with pore size in the nanometer region was fabricated on the a-SiC/Si substrates by the electrochemical etching method using HF/H2O/surfactant solution. Systematic study showed that the HF concentration in the etching solution (in the 1-73% region) strongly affects the structure (both the pore size and the pore density) of the porous a-SiC layer. It was also observed the changing of the photoluminescence properties of the porous a-SiC layer when its structure has been changed.

Journal of Physics: Conference Series, 2009

The study on co-deposition of Ni-nano SiC in sulphamate bath was conducted with different nano Si... more The study on co-deposition of Ni-nano SiC in sulphamate bath was conducted with different nano SiC concentrations from 1 to 20 g/l. The deposition of light inert SiC nanoparticles in Ni plating was investigated by scanning electron microscopy SEM and X-ray dispersive spectrometer EDX measurements. The microhardness and corrosion resistance were also measured to evaluate mechanical and corrosion properties of Ni-nano SiC coating on metal.

Journal of Physics: Conference Series, 2009

... Huynh Thi Ha1, Cao Tuan Anh2, Nguyen Thi Thu Ha1, Phan Viet Phong1, Dao Tran Cao1, Le Quang H... more ... Huynh Thi Ha1, Cao Tuan Anh2, Nguyen Thi Thu Ha1, Phan Viet Phong1, Dao Tran Cao1, Le Quang Huy1 and Nguyen The Quynh1 1 Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay Distr., Hanoi, Vietnam 2 ...

Journal of Physics: Conference Series, 2009

The study on co-deposition of Ni-nano SiC in sulphamate bath was conducted with different nano Si... more The study on co-deposition of Ni-nano SiC in sulphamate bath was conducted with different nano SiC concentrations from 1 to 20 g/l. The deposition of light inert SiC nanoparticles in Ni plating was investigated by scanning electron microscopy SEM and X-ray dispersive ...

Journal of Physics: Conference Series, 2009